[daip] APCAL error

[Eric Greisen]

Arnaud Collioud wrote:
> Dear AIPS developers,
> 
> I am processing the session RDV84 (Dec 2010) with 31DEC11 AIPS version. I am trying to build SN tables from GC and TY tables  (5 subarrays), but I am encountering an error with the task APCAL (see below).
> 
> APCAL1: Task APCAL  (release of 31DEC11) begins
> APCAL1: Writing SN table  1
> PCAL1: AMPCAL: NO GAIN FOR ANT:   3 POL: 1 IF:    3
> APCAL1: Purports to die of UNNATURAL causes
> APCAL1: localhos 31DEC11 TST: Cpu=      0.2  Real=      0  IO=        15
>
> 
> This problem only occurs for  the X-band and not for the S-band, where APCAL runs smoothly.
> 
> Data was imported with FITLD, then processed with VLBAFIX with subarrays determination. GC and TY tables were filled with the task ANTAB.
> Maybe something went wrong during ANTAB (even if I have no error message), but I do not know what (and I tried several times).
>

I have loaded the data but do not understand it well enough to separate 
into subarrays - at first load the S band and X band are each 4 IFs in 
an 8 IF data form.  APCAL generates this message when it is using a GC 
table and your GC table does not have data for antennas 3, 5, 6, 11, 15, 
and 16.  These are non-VLBA sites (HH, KB, KK, NY, TS, WZ).  APCAL uses 
the GC table when there are no appropriate values in the TY table and 
indeed your TY table has no values for the same set of antennas.  You 
will have to obtain data for these antennas from log files and enter 
them into AIPS, I believe via VLOG.  I am not a VLBI expert and our AIPS 
expert VLBI user is on vacation until June 20.  I will run this by some 
other folks and if they disagree with my answer, I will let you know.

Eric Greisen